Remove extensions::ServiceRegistrationManager.

extensions/test/test_service_registration_manager.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "extensions/test/test_service_registration_manager.h"
-
-namespace extensions {
-
-TestServiceRegistrationManager::TestServiceRegistrationManager() {
-  ServiceRegistrationManager::SetServiceRegistrationManagerForTest(this);
-}
-
-TestServiceRegistrationManager::~TestServiceRegistrationManager() {
-  ServiceRegistrationManager::SetServiceRegistrationManagerForTest(nullptr);
-}
-
-void TestServiceRegistrationManager::AddServiceToServiceRegistry(
-    content::ServiceRegistry* service_registry,
-    internal::ServiceFactoryBase* factory) {
-  auto test_factory = test_factories_.find(factory->GetName());
-  if (test_factory != test_factories_.end()) {
-    test_factory->second->Register(service_registry);
-  } else {
-    ServiceRegistrationManager::AddServiceToServiceRegistry(service_registry,
-                                                            factory);
-  }
-}
-
-}  // namespace extensions